School of the Sciences

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Identifying chlorhexidine and sodium hypochlorite reaction products and the environmental implications of its interaction with cotton fibers
(Dec-23) Huynh, Stacy 1997-; Beatty, John; Salazar, Gustavo; Lin, Shiru
Chlorhexidine is heavily used in the medical and dental field and is prescribed for multiple uses related to healthcare. When in contact with sodium hypochlorite, chlorhexidine breaks down into several toxic compounds that are not fully understood, and these compounds have impacts on the environment and human health, due to its heavy use in the medical field. Chlorhexidine breaks down into compounds that permanently adhere to and damage the cellulose fibers found in cotton fabrics and alter the visible quality of fabric, which leads to re-washing of fabrics or outright disposal of fabric due to the staining and damage. Chlorhexidine is also used in conjunction with sodium hypochlorite in dental procedures, such as root canals, and the toxic nature of this interaction is not fully understood. Previous studies have identified several products of this reaction, one being para-chloroaniline, suggesting that chlorhexidine should not be used in conjunction with chemical oxidizers like bleach until the toxic products are further studied and identified. Understanding how chlorhexidine interacts with textile fibers like cellulose will save water and cotton fabric from being prematurely disposed of and negatively impacting the environment. This project will work to understand the reaction between chlorhexidine and sodium hypochlorite, the toxic products that result from this reaction, and its interactions with cotton fiber textiles to reduce its impact on health and the environment.
Syntheses and characterizations of homoleptic and heteroleptic copper complexes with monocyclic and polycyclic azine ligands
(Dec-23) Kouadio, Halima; Omary, Manal; Mirsaleh-Kohan, Nasrin; Salazar, Gustavo
This thesis is concerned with the following ligands to use to coordinate and react to copper: a pyrimidine: niacinamide, the polyazine monocyclic triazine: cyanuric acid, and bicyclic N- donating hydrocarbons: quinoxaline and caffeine. When reacted with cuprous salts consisting of organic ligands they form multi-ligand coordination supramolecular architectures (1) or halides to form copper halide clusters. In the novel compounds, metal-metal interactions occur, which exhibit low-lying triplet state charge transfers, allowing the tunability of a photon-emitting compound which is expected to form the emission. Cuprous metal centers also possess the ability to self-assemble to form coordination polymers. Group 11 d10 coinage metals exhibit strong metal-to-ligand charge transfers (MLCT) as well.(50) Characterization of all compounds was completed using thermogravimetric analysis, X-ray crystallography, Fourier transform infrared spectroscopy (FTIR), and photoluminescence spectroscopy. The acquired data is analyzed and discussed further in the following thesis.
Synthesis and characterization of diverse copper halide complexes with a range of heterocyclic ligands
(Dec-23) Diaby, Aminata 1988-; Dr. Manal Omary; Mirsaleh-Kohan, Nasrin; Dr. Richard Sheardy
This study aimed to compare the stability, physical, and chemical attributes of Cu(I) and Cu(ACN) metals, investigating their resemblances and disparities. It comprises approximately 137 pages, encompassing 90 figures, 16 tables, and references. The research focused on synthesizing and characterizing Cu(I) complexes with azole family ligands. Two methodologies were applied: the first involving CuI and Cu(CH3CN) (where X = I or CH3CN) reacting with single ligands like 3,5-diisopropylpyrazole, 3,5-diphenolpyrazole, 3,5-(tert)-butylpyrazole, and 5-(4-chlorophenyl)-1H-tetrazole. The second utilized Cu(CH3CN) with mixed ligands specifically 3,5-diphenolpyrazole and pyrazine, as well as 3,5-(tert)-butylpyrazole and pyrazine. Complex synthesis occurred via solvent-mediated routes using the Schlenk technique and solvent-free reactions with mechanical grinding. Comprehensive characterization involved techniques such as melting point determination, solubility tests, luminescence spectroscopy, FT-IR, TGA, elemental analysis, NMR, and X-ray crystallography. Ligands were characterized using the same listed techniques to understand changes. All synthesized products underwent thorough characterization using diverse analytical tools.
HPLC analysis to assess efficacy of cisplatin, nedaplatin, and oxaliplatin
(Dec-23) Hernandez, Jessica 1990-; Mirsaleh-Kohan, Nasrin; Beatty, John; Salazar, Gustavo
Platinum drugs are one of the most widely used agents against cancerous cells. Cisplatin’s chemotherapeutic efficacy is limited by the increase of tumor resistivity and unwanted side effects. Cisplatin’s cytotoxicity is linked to its ability of forming 1,2-intrastrand adducts with adjacent guanine (G) bases. An analytical method to detect and quantify the amount of platinum bound to DNA is necessary to enhance and develop anticancer drugs. In this work, High Performance Liquid Chromatography (HPLC) analysis was performed to assess the binding of cisplatin, nedaplatin, and oxaliplatin to the dinucleotide dGpdG. By examining the concentration ratios and incubation periods at 37 °C, we measured the amount of platinum drug reacted with DNA (platination rates) indicating the percentage of Platinum-DNA (Pt-DNA) adducts. Cisplatin proved to be the most effective, followed by nedaplatin, and then oxaliplatin. This research has implications in designing more efficient anticancer drugs.
Synthesis of doxorubicin-protein conjugates via cobalt coordination chemistry
(May-23) Colion, Sara; Petros, Robby; Beatty, John; Mirsaleh-Kohan, Nasrin
The use of nanotechnology-based drug delivery systems in the context of cancer treatments has the potential to help target drug chemotherapeutics to tumor cells more precisely while simultaneously reducing off-target toxicity. One of the most prescribed chemotherapeutics, doxorubicin, is an anthracyclines drug that is effective in treating cancer; however, the drug exhibits dose-limiting cardiotoxicity. Dox intercalates DNA, resulting in the deterioration of DNA strands and the ultimate inhibition of DNA and RNA synthesis. Doxorubicin’s chemical structure contains a primary amine group that can be used to crosslink it to a protein. This project focuses on using cobalt coordination chemistry as a novel crosslinking strategy to synthesize conjugates of Dox bound human serum albumin (HSA). The synthesis of conjugates of Dox with HSA will be discussed along with methods for characterization via HPLC that allow the number of Dox molecules bound per protein molecule to be determined.
Fourier transform: Constructing and deconstructing overtones
(May-23) Wiersema, Lukas; Navarra-Madsen, Junalyn; Smith, Shawnda; Falley, Brandi
The purpose of this thesis is to examine why different instruments sound different even when playing the same note. This is done through the use of the Fourier transform on sample recordings of different instruments. The thesis will include a bases for understanding waves and how the Fourier transform is used, as well as some basic music theory, before examining the differences in the instruments.
Thermomyces Lanuginosus Xylanase Unfolds to a Structure with Large Random Coi Content Below 24 $#730;C AT pH 7.0
(1/1/2013) Arrington, Tara M.; Britt, Billy M.; Sheardy, Richard Dean; Rawashdeh-Omary, Manal
Thermomyces lanuginosus xylanase is a thermophilic enzyme with maximum activity at 55 °C. Previous work in our laboratory has determined that it undergoes a large conformational change at 24°C involving a volume change of approximately 190 L/mol upon going from the physiological-temperature conformer to the low-temperature conformer. This value was determined through previous research from our laboratory using the Clapeyron equation. Our current investigation is to determine whether this protein is fully unfolded or exists as a molten globule below the transition temperature. Our methods for detection are dynamic light scattering, differential scanning calorimetry and circular dichroism. We found that the structure is best characterized as random coil rather than molten globule below 24 °C.
Assessment of focal complexes in B35 Neuroblastoma growthcones following Lovastatin treatment
(1/1/2013) Deshmukh, Shweta Dilip; Hynds, DiAnna L.; Uphouse, Lynda L.; Beck, Brian W.
Proper development of the nervous system requires efficient and precise axon growth and guidance, growths requiring dynamic focal complex adhesion and de-adhesion in the neuronal growth cone. The formation of focal complexes is regulated in part by guanine triphosphatases (GTPases) of the Rho family, which signal bi-directionally to focal complex constituents. Rho GTPases are also regulated through binding of guanosine triphosphate (GTP), a process facilitated by membrane targeting through geranylgeranylation (a specific type of prenylation) at their C terminus. Prior work in our laboratory demonstrated that decreasing geranylgeranylation with the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG CoA) reductase inhibitor, lovastatin, decreases neurite initiation and increases neurite branching and cell body rounding. These effects were reversed by co-treatment with geranylgeraniol, a precursor for geranylgeranylation. In the current work, we determined whether manipulating protein prenylation decreases the association of focal complex proteins (paxillin, talin or vinculin) with β1-integrin in B35 growth cones. B35 neuroblastoma cells were grown on uncoated glass coverslips, or coverslips coated with 25 μg/ml laminin or collagen. Cells were maintained in media were either not treated, or treated with lovastatin (LOV, 20 μM) alone or in combination with geranylgeraniol (GGOH, 10 μM). Focal complex formation in growth cones on the different substrata was assessed using co-immunoprecipitation and double-label immunocytochemistry. Culturing on different substrata did not alter the amount of paxillin or talin that associated with 1 integrin. However, vinculin co-localization with 1 integrin was decreased for cells plated on collagen or laminin; and co-localization with talin was increased in cells cultured on laminin, compared to cells plated on uncoated coverslips. For cells plated on collagen, GGOH decreased the amount of paxillin, but not talin or vinculin, that co-localized with β1 integrin compared to control cells maintained in reduced serum medium or treated with LOV. For cells cultured on their native, secreted substratum (undefined) or laminin, manipulating geranylgeranylation did not alter the association of focal complex proteins with 1 integrin in whole cell lysates, growth cones or cell bodies. However, treatment to alter protein geranylgeranylation (LOV, GGOH, LOV+GGOH) decreased the amount of co-localization of paxillin and talin, and GGOH treatment decreased the amount of vinculin co-localized with 1 integrin in growth cones, compared to cells in reduced serum medium (SCM) for cells cultured on collagen. Together, we interpret these data to indicate that inhibiting protein prenylation decreases growth cone focal adhesions, likely leading to decreased neurite initiation. Understanding the molecular mechanisms that regulate Rho GTPase control of neuronal process extension will facilitate our understanding of nervous system development, as well as identify potential therapeutic targets for treating developmental, traumatic and degenerative neural lesions.
Strain Differences in Fluoxetine-Induced Sexual Dysfunction
(1/1/2013) Miryala, Chandra Suma; Uphouse, Lynda; Hynds, DiAnna L.; Mills, Nathaniel; Beck, Brian; Fuchs, Janon
The present experiments were designed to examine strain differences in sexual dysfunction after acute fluoxetine treatment. Female Fischer and Sprague-Dawley rats were used. Three major experiments were performed. (1) Strain differences were examined in regularly cycling female rats and in ovariectomized rats hormonally primed with 0.067 µg/g estradiol benzoate and 3.333 µg/g progesterone following treatment with 5, 10, 15, 20 or 30 mg/kg fluoxetine. (2) The effects of the 5-HT2 receptor antagonist, ketanserin 0.416, 0.5, 1, 2, 5 or 10 mg/kg, were compared in the two strains. (3) The combination of 10 mg/kg fluoxetine and l mg/kg ketanserin was examined. The major outcomes of this study were: (i) consistent with prior studies, fluoxetine reduced female rat sexual behavior in both hormonally-primed, ovariectomized and in naturally cycling rats; (ii) hormonally primed, ovariectomized rats were more sensitive to the lordosis inhibiting effects of fluoxetine than the intact, naturally cycling females; (iii) in both hormonally-primed and naturally cycling rats, Sprague-Dawley females were less sensitive to the lordosis-inhibiting effects of fluoxetine than Fischer females; (iv) a 5-HT2A/2C receptor antagonist, ketanserin, reduced lordosis behavior in both strains with a slightly greater effect in Sprague-Dawley females, but the difference was modest in comparison to the strain differences in response to either fluoxetine, and (v) the combination of fluoxetine and ketanserin did not amplify negative effects on lordosis behavior relative to the individual drugs alone. From these experiments, it was concluded that Fischer female rats are more sensitive than Sprague-Dawley females to the lordosis inhibiting effects of fluoxetine and that the 5-HT2 receptor, may not be involved. Potential mechanisms responsible for strain differences in the receptor activation are discussed.
Flags of Caution for Future Downturns in the Housing Market Prediction Using the Markov Chain Model
(1/1/2013) Owens, Susan Eustice; Marshall, David; Edwards, Don; Demuynck, Marie-Anne; Ingram, Paul
The recent downturn in the United States housing market yielded a period of time akin to that of the Great Depression. Since the 1930s, there has never been an economic downturn in this country as close as that of the Great Depression era. The Depression experienced similarities to the current economic crisis but more important, the Great Depression's comparable statistical data raise flags of caution for future downturns in the housing market. One of the major similarities is a housing boom, which in both periods preceded a downturn. Precipitous growth reached unsustainable levels; then, a big decline burst the real estate bubble. In this study the Markov Chain Model was used as a forecasting tool to evaluate the status of home mortgages and to demonstrate the capability to predict future housing economic crises. Statistical data from both eras were gathered and shown in a transition matrix.
Predicting Total Student Credit Hours Production by Cohort Stratification
(Texas Woman s University, 1/1/2013) Sheeder, Carolina Dominguez
The objective of this study is to develop predictive models of total student credit hours (SCH) prior to the fall semester of interest by using preregistration data from Texas Woman's University (TWU). We developed two different approaches to predict SCH for undergraduate and SCH for graduate students separately. Our first approach is based on the patterns of weekly counts of SCH observed over time. For our second approach, we developed a model that relies on an average of SCH and a total headcount. This research presents a self-contained procedure to predict headcount and includes a criterion to select a prediction model for the average of SCH. After explaining the development of each of our SCH prediction models, we compare the results and discuss their strengths and weaknesses.
A Statistical approach to predict future members of the Baseball Hall of Fame
(Texas Woman s University, 1/1/2013) Zemler, Kelsey; Marshall, David, Ph. D.; Hamner, Mark S.; Edwards, Don E.; Navarra-Madsen, Junalyn
The purpose of this study was to construct an accurate statistical model for the members of the baseball hall of fame and use this model to predict future hall of fame members, using a frequentist approach. Using logistic regression, accurate models were determined for each position that can be used to predict if a certain player will make it into the Hall of Fame. Baseball-Reference.com was the major source of data. Once the analysis was complete, nine different models were chosen to determine the probability that a certain player at a given position would make it into the Hall of Fame based on their baseball statistics. Positions were also analyzed by time periods and models were found for each position in each time frame, if one existed. In general, time period models for the various positions were inconclusive, however a model for each position was found overall.
Sunflowers and Honeybees: A Study of the Mutualistic Relationship from a Biochemical and Morpho-Anatomical Perspective
(1/1/2013) Wojtaszek, Jennie W.; Maier, Camelia; Conrad-Webb, Heather; Beck, Brian; McIntire, Sarah
The mutualistic relationship between Helianthus annuus (Asteraceae) and Apis mellifera is reflected in their co-evolutionary adaptations. The corolla morphology and pigmentation of sunflowers help form a target pattern under UV, recognizable by bees. While collecting rewards, bees cross-pollinate the disk florets. Morpho-anatomical co-adaptations of the sunflower and honeybee were studied with LM, SEM, and CLSM. This study reports for the first time the presence of one to three rows of transitional papillae on stigma, which may function in protection of the receptive stigma from self-pollination. A model of the cross-pollination of sunflower inflorescence by honeybees is presented. The chemical characterization of flavonoid pigments in disk florets, known to contribute to the target pattern of the inflorescence, accomplished with chromatographic and MS techniques, revealed the presence of luteolin and pelargonidin pigments. This is the first report on the presence of luteolin and pelargonidin in sunflower disk florets. Results of this study will contribute to the metabolomics of the phenylpropanoid pathway in H. annuus in addition to enhancing understanding of mutualism and biosemiotic relationships between flowering plants and pollinators.
Regulation of Expression of the M143 Promoter of Mouse Cytomegalovirus
(1/1/2013) Eluru, Seneetha Reddy; Hanson, Laura K.; Conrad-Webb, Heather; Mills, Nathaniel C.
The objective of this research is to examine the regulation of an essential gene (m143) in MCMV that has sequence and functional homology to HCMV genes IRS1/TRS1. All of these prevent the shutdown of protein synthesis that is an antiviral defense. Little is known about the regulation of these genes at either the transcriptional or posttranscriptional levels. Sequential deletion mutant analysis of the m143 promoter was done in the context of an SEAP reporter plasmid. The results indicated that viral proteins are required for activation and the presence of repressor-binding sites and activation-binding sites. EMSA shows that SP1 may be important for the activation. Two important viral transcriptional regulators IE1 and IE3, each alone weakly activates the m143 promoter, but together synergize to efficiently activate this promoter. The absence of repression with co-transfection experiments support repression by other viral proteins. Such studies may lead to novel treatments for cytomegalovirus infection.
Understanding the conformations and stabilities of g-quadruplexes formed by human telomere sequence in ideal and less ideal solutions
(1/1/2014) Sharma, Vishal Rajat; Sheardy, Richard Dean; Mirsaleh-Kohan, Nasrin; Rawashdeh-Omary, Manal
The G-rich termini of human chromosomes, called telomeres, have the ability to form unique DNA structures called G-Quadruplexes, which have been implicated in certain cancer types and, as a result, have drawn researchers' attention to study their structure inside the cell and thus consider them as potential targets for new anticancer therapies. Biophysical studies of these entities have been carried out under near ideal conditions, i.e., low phosphate concentration (e.g., 10mM), pH 7, low ionic strength (e.g., 115mM), and for optical studies, low concentration of DNA (e.g., 1 × 10-6 M). We, here, created less ideal conditions by using different osmolytes such as polyethylene glycol, acetonitrile, trifluoroethanol, and betaine. Our research focuses on the effect of these co-solutes on the structural and thermodynamic properties of telomeric DNA oligomers and report the characterization of (TTAGGG)x, where x = 1, 2, or 4. In general, increasing the percentage of any osmolytes in solutions drives the equilibrium from unimolecular hybrid to multimolecular parallel conformation. In addition, Stability of parallel conformation also increases.
Analyzing trends in baseball Hall of Fame voting, through the use of Multidimensional Scaling
(1/1/2014) Porter, Kalli Cherie; Marshall, David; Falley, Brandi; Edwards, Don E.
The purpose of this study was to see if any trends exist within voting on the baseball Hall of Fame ballot. For this particular study I used the mathematical concept called Multidimensional Scaling. This approach allowed me to visually see the difference between players in relation to the number of votes received. The majority of the data obtained for this study was through the Baseball Writers' Association of America website and the National Baseball Hall of Fame and Museum website. Through the use of Multidimensional Scaling and R programming, I was able to construct two dimensions within the voting on the ballot. It was decided that characteristics pertaining to certain players make an impact on the number of votes received.
Benford's law and humanly generated prices in auction houses and buyout systems of virtual worlds
(1/1/2014) Endress, Megan Brooke; Marshall, David; Falley, Brandi; Wheeler, Ann
The purpose of this study was to analyze the buyout, or "buy now," prices in auction houses of virtual environments, such as World of Warcraft and Guild Wars 2. Human players interact with an auction house user interface in order to buy or sell in-game items, purchasable with in-game currency. Players wishing to sell items can post their items on the auction house for set lengths of time, as well as set a starting bid amount and/or an amount in which other players can instantly buy the item. Since the establishment of Benford's Law, it has been supported that data generated by humans typically does not follow Benford's Law, proving to be a beneficial tool in detecting fraudulent accounting data. However, this study shows that the leading significant digits of these buyout prices in virtual environments created by humans follow Benford's Law by utilizing Kuiper's goodness of fit V_n test, a modified Kolmogorov-Smirnov test.
Historic development of prime numbers
(1/1/2014) Ryder, Brent Alan; Grigorieva, Ellina; Edwards, Don E.; Marshall, David
The purpose of this thesis is to investigate the history of prime numbers and development of prime number theory. There are three major sections to this thesis, Ancient times, Dark Ages, and Modern times. The ancient time's section has topics on the `Ishango Bone', `Rhine Papyrus' with an investigation of Egyptian fractions, and Euclid's Elements where the proof of the existence of an infinite number of primes was first given. The `Dark Ages' section has topics on non-European mathematicians who worked with prime numbers. The final section covers more modern prime number theory from Gauss, Fermat, Legendre, and Riemann.
Calcium-dependent global chromatin compaction protects DNA from UV inflicted damage
(1/13/2020) Abbas, Mohammad M; Bergel, Michael
Eukaryotic genomes are packaged into chromatin, which is the physiological substrate for all DNA-mediated functions, including DNA damage repair. At the DNA damage site, chromatin organization undergoes critical rearrangements during the repair process. These rearrangements around the lesion sites accommodate at least three steps: providing access to the repair factors, repair, and restoring the DNA’s pre-lesion. chromatin architecture. However, the global changes to chromatin after UV-irradiation were less explored and understood. To investigate the relationship between chromatin condensation and UV irradiation, HeLa-S3 cells were irradiated and subjected to micrococcal nuclease digestion analysis. The results showed that chromatin globally commenced compaction five minutes after UV-irradiation. Twenty-four hours after irradiation chromatin returned to the pre-UV steady-state. Southwestern blots showed that cells were irradiated twice at 15 J/m2 with a five minutes break had a significantly lower cyclobutane pyrimidine dimers (CPD) and DNA (6-4) photoproduct (6-4PP) rate in comparison to cells subjected to 30 J/m2, and had no significant difference from cells irradiated with a single dose of 15 J/m2. Western blot analysis demonstrated a post-UV core histone deacetylation wave which followed the chromatin condensation. Western blots analysis of caspase-3, which is activated in apoptotic cells both by extrinsic and intrinsic pathways, showed no caspase-3 activation after five and ten minutes post UV-irradiation. Here, we demonstrate that an environmental genotoxic agent, UV radiation, causes immediate and global chromatin compaction in HeLa cells and this compaction results in a robust reduction in the newly formed lesions. Our data suggest an influx of calcium cations after UV irradiation is directly involved in inducing chromatin compaction.
Analysis of factors contributing to student’s academic performance in college’s STEM program
(1/18/2022) Ayeni, Abimbola A; Falley, Brandi
The purpose of this study is to analyze different variables in understanding how they affect the academic performance of students taking STEM courses at a mid-sized college in the southern United States. These factors are classified into pre-college variables and college variables. The pre-college variables are ACT/SAT scores, gender, ethnicity, and first-generation student or not. The college variables are college GPA, Pell grant recipient, the student’s continuance with the degree major in sophomore year. Implementing regression analysis and using backward regression to remove variables that are not correlated to the response variable (CGPA), we were able to arrive at the best model using the three variables: ACT mathematics, ACT English, and gender. The resulting variables selected show us how the value of R^2 has helped us in making sense of the model selected by 14.2%.

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